If the key does not match or no keystone is held at all when the gate is activated, it will be as if the keyed gateway doesn't even exist.
tested today on the 13.1 patreon server, the advanced stabalizer no longer appears over my player, the pages of the compendium after page 4 show with no content other than page title.
Dota Plus:--* Added a new Summer Terrain* Added a new Plus in-game prediction charm, grants you increasing amounts of shards for correct predictions in a row (10/20/30/40/50 for 1/2/3/4/5x, 50 for subsequent)* Added a new feature to let Plus members spectate their friends' games live, seeing only what their friend's team can see.
You can join in any time the game is ongoing.* Added dozens of new Hero Quests* Playing Turbo games now grants half the normal hero xp for wins/losses, rather than none.* Added a new global Hero Trends page* You can now purchase some Tools for shards in the Plus Rewards store.* Fixed a bug that would sometimes cause Plus guides to get stuck and not work.* Improved the item/ability/lane suggestions* Plus item suggestions now default to the first suggestion, with a button to examine alternatives.* The full popular items list is now shown even when you have a specific sequence selected.
Once you reach the end of the list, the next jump will take you back to the first gate in the network.
Essentially, putting a keystone into the gateway puts the gateway into its own network.